Air pump



July 15,1924. 1,501,546

F. B. SHAW AIR PUMP Filed Aug. 25, 1922 Wan/t B Shcmr attorney" Patented July 15, 1924.

FRANK B; sum, or cAn nonIA, MICHIGAN, Assrenfon. or onn-rinrir 'ro o'L'Ynn e.

PIERSON, or WAYLAND, MICHIGAN.

Am PUMP.

Application filed August 25, 1922. Serial No. 584,228.

To all whom it may concern Be it known that I, FRANK B. SHAW, a citizen of the United States, residing at Caledonia, Kent County, Michigan, have invented certain new and useful Improvements in Air Pumps, of which the following by the devices and means described in the following specification. The invention is clearly defined and pointed out in the claims. I

A structure which is a preferred embodiment of the invention is clearly illustrated in the accompanying drawing forming a part of this specification, in which:

Fig. I is a side elevation of my improved pump, a portion of the cylinder being broken away.

Fig. II is a vertical section'on a line corresponding to line 2-2 of Fig. I, the parts being shown in full lines for convenience in illustration.

Figure III is a detail vertical section on a line corresponding to line 33 of Fig. II.

In the drawing the sectional views are taken looking in the direction of the little arrows at the ends of the section lines and similar numerals of reference refer to similar parts throughout the several views.

Referring 'to the drawing, I provide a base 1 having foot extensions 2 at opposite sides and a discharge 3. The cylinder 4 is preferably a piece of drawn tubing suitably secured to the base and is provided with a head 5 having an air inlet opening 6. The metallic piston 7 is provided with a plurality of annular piston ring grooves 8 for the resilient metal piston rings 9, these rings being preferably provided with lap-joints 10. The piston has a recess 11 at its lower end and a central longitudinal bore 12 shouldered at its lower end toprovide the valve seat 13.

The passage 14 leads from the top of the piston to the bore 12. The disk valve 15 is also of metal and is provided with a stem 16 engaging an opening 17 in the strap-like valve support 18 which is secured within the recess 11 by the screws 19. The weightof the valve holds it normally in open position by the pressure ofthe air on the down stroke causing it to. seat.

The piston rod 21 is threaded into the piston and secured therein by the pin 20. The piston rod reciprocates to an opening 22 in the head and is guided thereby.

-My improved air pump is especially designed by me as av tire pump and I have shown the same as embodied for such use. The parts being all formed of metal are not liable to become inoperative as is the case with leather or fabric plungers or valves on account of drying out or rotting occasioned by lubricant.

Having thus describedmy invention what I claim as new and desire to secure by Letters Patent is:

1. A structure of the class described comprising a cylindrical metal piston provided with a piston ring and having a recess in its lower end with a central bore extending therefrom and shouldered to provide a downwardly facing valve seat, there being a passage leading from the upper end of said piston to said bore, a metal disk valve having a downwardly projecting stem, and a strap-like valve holder secured within said recess across said valve seat and having a guide opening for said stem.

2. A structure of the class described comprising a cylinrical metal piston provided with a piston ring and having a longitudinal air passage with a. valve seat at its lower end, said piston being recessed around said valve seat, a metal disk valve coacting with said seat and having a downwardly projecting stem, and a valve holder disposed in said recess to extend across said seat and having a guide opening therein for said stem.

3. A structure of the class described comprising a cylindrical metal piston having a recess in its lower end and a central bore within said recess across said valve seat and extending therefrom and shouldered to pro having a guide opening for said stem, and a vide a downwardly facing valve seat, there piston rod threaded centrally into the upper 10 being a passage leading from the upper end end of said piston.

of said piston'to said bore, a metal disk In Witness whereof, I have hereunto set valve having a central downwardly project my hand and seal.

ing stem, a strap-like valve holder secured FRANK B. SHAW. [n s.] 

